 The Study and Core Area boundaries define the "historic landscape" of the battlefield while areas that retain integrity define the "modern landscape".For example, if a particular farm field was important during the battle but now is covered by a housing development, it would still be included in a Core or Study Area boundary because the farm field informs the history of the battle.That same farm field, however, would not be considered for inclusion in an POTNR boundary because it no longer has integrity (i.e.